[Asterisk-Users] attended transfer issue

[Eric "ManxPower" Wieling]

Damon Estep wrote:
> There is some kind of issue with SIP transfer interaction between some
> SIP phones and asterisk, I have personal experience with Polycom phones
> not being able to do a blind xfer using the feature key.
> 
> We have to use the asterisk # blind xfrer functionality for blind
> transfers
> 
> The phones will drop the call if you initiate a transfer with the
> feature key but do not wait for the remote line to answer before
> releasing the call. In other words, if you hit transfer on the phone,
> wait for the remote phone to ring, and hang up, you will drop the call.
> 
> If you wait for the remote phone to answer (live or voicemail) the
> transfer will complete.

My users also reported this.  It turns out Polycom added a Blind soft 
key to continue with a blind transfer.  If you don't select that then a 
blind transfer will fail.